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T Révész

Publications and source records attributed to T Révész.

At least 19 recordsLinked to original sources
PubMed2005

How to improve the search for an unrelated haematopoietic stem cell donor. Faster is better than more!

Many patients do not reach haematopoietic stem cell transplantation. Shortage of unrelated donors (UDs) is still seen as the main cause. However, with a worldwide UD pool containing more than 8 million donors, it is possible that other impediments are becoming more important. We analysed 549 UD searches for Dutch patients, performed between 1987 and 2000, in order to find the reasons for failure or success to reach transplantation. Between 1996 and 2000, 59% of the patients of Northwest European origin received a graft from an UD with a median time span of 4.4 months from the start of the search. In all, 11% of the patients lacked a compatible donor, while 30% became medically unfit for transplantation. This is in contrast to the patients of non-Northwest European origin for whom UD shortage is still the most important impediment; only 32% were transplanted while 50% lacked a compatible donor. We conclude that the shortage of donors is no longer the biggest constraint in unrelated stem cell transplantation for patients of Northwest European origin. It may be more effective to optimize the chance on transplantation by making the search process more efficient.

Data Collection↗
PubMed2005

Donor leukocyte infusion after hematopoietic stem cell transplantation in patients with juvenile myelomonocytic leukemia.

Juvenile myelomonocytic leukemia (JMML) is a clonal myeloproliferative disorder of early childhood. In all, 21 patients with JMML who received donor leukocyte infusion (DLI) after allogeneic hematopoietic stem cell transplantation (HSCT) for either mixed chimerism (MC, n=7) or relapse (n=14) were studied. Six patients had been transplanted from an HLA-matched sibling and 15 from other donors. Six of the 21 patients (MC: 3/7 patients; relapse: 3/14 patients) responded to DLI. Response rate was significantly higher in patients receiving a higher total T-cell dose (> or =1 x 10(7)/kg) and in patients with an abnormal karyotype. None of the six patients receiving DLI from a matched sibling responded. Response was observed in five of six patients who did and in one of 15 children who did not develop acute graft-versus-host disease following DLI (P=0.01). The overall outcome was poor even for the responders. Only one of the responders is alive in remission, two relapsed, and three died of complications. In conclusion, this study shows that some cases of JMML may be sensitive to DLI, this providing evidence for a graft-versus-leukemia effect in JMML. Infusion of a high number of T cells, strategies to reduce toxicity, and cytoreduction prior to DLI may improve the results.

Child↗
PubMed2003

[Invasive infection with Moraxella catarrhalis in two children with lymphatic leukemia and granulocytopenia].

In two young children with leukaemia, a girl and a boy aged 5 and 4 years, respectively, an invasive infection due to Moraxella catarrhalis was diagnosed at the time of granulocytopenia. They were treated with antibiotics. The first child developed pneumonia and recovered, the other developed severe septic shock and died. M. catarrhalis is a Gram-negative diplococcus, frequently colonising the upper respiratory tract in young children. In childhood this pathogen mainly causes infections such as otitis media and sinusitis, while in adults it primarily causes laryngitis, bronchitis and pneumonia. Immunocompromised patients or patients with chronic cardiopulmonary disease have an increased risk of severe infections.

Agranulocytosis↗
PubMed2003

[Splenectomy in children; indications and surgical aspects].

There are no hard indications for splenectomy in children. The single most generally accepted indication is the more severe form of congenital spherocytosis. Idiopathic thrombocytopenia purpura is only an indication if there is a severe bleeding tendency. Other than local conditions involving the spleen, there seem to be no good indications for partial splenectomy. Ablation by means of embolisation has not gained popularity. Laparoscopic splenectomy appears to be better than splenectomy via laparotomy, but sound scientific evidence for this is not yet available. There appears to be an increased incidence of portal vein thrombosis immediately after splenectomy. The value of thrombosis prophylaxis has not yet been investigated.

Child↗
PubMed2003

[Fulminating pneumococcal septicemia in a 2 year old child with sickle cell anemia].

A 2-year-old boy known with homozygous sickle cell anaemia became acutely ill at home. Despite intensive care, he died a few hours later due to pneumococcal septicaemia. In young children with homozygous sickle cell anaemia, spleen function is already severely impaired in childhood due to haemolysis and frequent vaso-occlusive episodes. These children therefore have an elevated susceptibility to severe invasive infections with encapsulated bacteria. Vaccination against pneumococci at-2 years of age, re-vaccination every 3-5 years, and antibiotic prophylaxis until 5 years of age, and thereafter with possible infections, are therefore necessary.

Anemia, Sickle Cell↗
PubMed2003

Eye shielding during total body irradiation for bone marrow transplantation in children transplanted for a hematological disorder: risks and benefits.

This is a retrospective analysis of 188 children who underwent total body irradiation (TBI) in one or two fractions before bone marrow transplantation (BMT) for a hematological disorder. While 139 children had eye shielding during TBI to decrease cataract formation, 49 did not. The blocks used for shielding caused cylindrical areas of decreased dose intensity in the brain. The aim of the study was to determine if there was an increased risk of relapse in the eyes or in the CNS after shielding of the eyes. The probability and severity of cataract formation with and without shielding were also evaluated. None of the 49 children without shielding had a relapse in their eyes or in the CNS after BMT. Of the children with shielding, none had a relapse in the eyes but two of the 139 (1.4%) had a CNS relapse. The incidence of cataracts without shielding was 90% (19 of 21 evaluable patients), while with shielding it was 31% (20 of 64). Severe cataracts were present in eight of 21 (38%) patients without and two of 64 (3%) patients with shielding. The probability of staying cataract free for at least five years was 0.77 with and 0.33 without shielding, at 8 years it was 0.53 and 0.24 respectively. The relative risk of developing a cataract without shielding vs shielding was three (95% CI=1.5; 5.9). It appears that the incidence of relapse in the eyes and CNS is not increased when the eyes are shielded during TBI. Shielding increased the latency time of cataract formation and decreased the severity of cataracts.

Adolescent↗
PubMed2003

Study of the role of Chlamydia, Mycoplasma, Ureaplasma and other microaerophilic and aerobic bacteria in uterine infections of mares with reproductive disorders.

In six healthy mares and 24 mares showing reproductive disorders swab samples were taken from the fossa clitoridis to isolate Taylorella equigenitalis, and from the uterus to isolate mycoplasmas, ureaplasmas and other aerobic bacteria. Swab samples were also taken from the uterus for Chlamydia antigen ELISA and Chlamydia PCR studies. The uterus of 27 mares was examined cytologically, and biopsy samples were taken from the endometrium for histological examinations and for immunohistochemical examinations aimed at the detection of chlamydiae. T. equigenitalis, mycoplasmas, ureaplasmas and chlamydiae could not be detected from any of the mares examined. Aerobic facultative pathogenic bacteria were isolated from mares with endometritis in four cases. In 18 out of 22 mares with endometritis (82%) no infective agents could be demonstrated. Further studies are needed to elucidate the relative importance of non-infectious causes of endometritis and of anaerobic bacteria often detectable in the uterus in the aetiology of the reproductive disorders observed.

Animals↗
PubMed2002

[Children with fever peaks and bone and joint pain: systemic juvenile idiopathic arthritis or acute lymphoblastic leukemia after all?].

In two 3-year-old infants, a girl and a boy, systemic juvenile idiopathic arthritis was suspected because of daily fever peaks, signs of polyarthritis and general malaise. Drug treatment was unsuccessful, and after extensive laboratory investigation acute lymphoblastic leukaemia (ALL) was diagnosed and treated adequately. ALL is the most common malignancy in childhood. About one-third of the patients present with joint or bone pain and fever. In this group of children, it can be difficult to identify ALL because it may mimic the clinical picture of systemic juvenile idiopathic arthritis and because of the possibility of a normal blood count at presentation. ALL should always be considered in the differential diagnosis in children with musculoskeletal pain and fever, even in the face of a normal blood count. In any case, a bone-marrow examination should be done before steroid treatment is given.

Arthralgia↗
PubMed2001

Evidence for pathological involvement of the spinal cord in motor neuron disease-inclusion dementia.

Fronto-temporal dementia (FTD), characterised pathologically by ubiquitinated inclusions in the hippocampal dentate fascia and fronto-temporal cortex, may develop in association with motor neuron disease (MND). However, FTD with identical pathological hallmarks may occur in isolation and has been termed motor neuron disease-inclusion dementia (MND-ID). We studied the pathology of three cases of MND-ID including the spinal cord, which has not previously been examined in this condition. The ages of the patients at death were 53, 70 and 68 years and the onset of FTD 10, 15 and 9 years before death. Neuropathological findings in all cases included micro-vacuolation in cortical layer II and ubiquitinated intraneuronal inclusions in fronto-temporal cortex and hippocampal dentate fascia. One case showed unusual basophilic, ubiquitinated neuronal cytoplasmic inclusions in the brain stem. Qualitative assessment of the spinal cord was normal in two cases, while the third showed mild pallor of the lateral cortico-spinal tracts and ubiquitinated inclusions in motor neurons typical of MND. Morphometry did not reveal any significant loss or decrease in size of anterior horn motor neurons. The results of this study are consistent with the hypothesis that the pathological changes of pure MND and MND-ID form a spectrum and demonstrate that pathological involvement of the motor system may occur in MND-ID without clinical evidence of MND.

Aged↗
PubMed2001

Sequence, genomic structure and tissue expression of Human BRI3, a member of the BRI gene family.

The BRI3 gene is a member of the BRI gene family, made up of at least three different genes (BRI1-3). Previous studies established the cDNA sequence and structure of the human and mouse BRI1 and BRI2 genes and we recently reported that mutations in the BRI2 isoform, located on chromosome 13, are associated with dementia in humans. In the present work, we determine the complete cDNA sequence and genomic organization of the human BRI3 gene. BRI3 codes for a polypeptide of 267 amino acids, with a Mr of 30 KDa and a pI of 8.47. The amino acid sequence is 43.7% identical to the sequence of the human BRI2, and 38.3% identical to that of human BRI1, with the highest percentage of amino acid identity being concentrated on the C-terminal half of the molecules. In Northern blots, BRI3 cDNA hybridizes only one message of approximately 2.1 kilobases, which is predominantly present in the human brain. The BRI3 gene is localized on chromosome 2 and consists of six exons spanning more than 20 kb. Homology search of EST data banks retrieved a Caenorhabditis briggsae homolog of BRI, indicating that the BRI gene belongs to a strongly conserved gene family. These studies, aimed at characterizing the members of the BRI gene family, may provide valuable clues to the understanding of their normal function and how mutations in BRI2 can cause neurodegeneration and dementia similar to Alzheimer's disease.

Alternative Splicing↗
PubMed2001

Spectrum of perforin gene mutations in familial hemophagocytic lymphohistiocytosis.

Familial hemophagocytic lymphohistiocytosis (FHL) is an autosomal recessive disease of early childhood characterized by nonmalignant accumulation and multivisceral infiltration of activated T lymphocytes and histiocytes (macrophages). Cytotoxic T and natural killer (NK) cell activity is markedly reduced or absent in these patients, and mutations in a lytic granule constituent, perforin, were recently identified in a number of FHL individuals. Here, we report a comprehensive survey of 34 additional patients with FHL for mutations in the coding region of the perforin gene and the relative frequency of perforin mutations in FHL. Perforin mutations were identified in 7 of the 34 families investigated. Six children were homozygous for the mutations, and one patient was a compound heterozygote. Four novel mutations were detected: one nonsense, two missense, and one deletion of one amino acid. In four families, a previously reported mutation at codon 374, causing a premature stop codon, was identified, and, therefore, this is the most common perforin mutation identified so far in FHL patients. We found perforin mutations in 20% of all FHL patients investigated (7/34), with a somewhat higher prevalence, approximately 30% (6/20), in children whose parents originated from Turkey. No other correlation between the type of mutation and the phenotype of the patients was evident from the present study. Our combined results from mutational analysis of 34 families and linkage analysis of a subset of consanguineous families indicate that perforin mutations account for 20%-40% of the FHL cases and the FHL 1 locus on chromosome 9 for approximately 10%, whereas the major part of the FHL cases are caused by mutations in not-yet-identified genes.

Amino Acid Substitution↗
PubMed2001

Extramedullary infiltrates at diagnosis have no prognostic significance in children with acute myeloid leukaemia.

This retrospective study was designed to review the relative frequency and prognostic significance of extramedullary infiltrates in children with acute myeloid leukaemia (AML). The registration data and initial discharge summaries were reviewed for all children diagnosed with AML, and registered by the Dutch Childhood Leukaemia Study Group (DCLSG). Between 1972 and 1998, 477 children were diagnosed with AML. Of these patients, 120 (25.1%) had extramedullary leukaemia (EML) at diagnosis. Four categories of EML were found: skin, soft tissue or bone, gingival infiltration and central nervous system (CNS) involvement. Patients who presented with gingival infiltrates, were older than those without EML or those in the other EML subgroups, had a high initial WBC count and a high proportion of M4/M5 morphological variants. This type of presentation could indicate a special biological entity. Univariate analysis of prognostic factors in patients treated after 1985 with intensive protocols showed that initial WBC count and the presence of favourable cytogenetic findings were significant. The presence of EML at diagnosis had no significant effect on event-free survival. In a stepwise multiple regression analysis only favourable cytogenetic findings remained significant.

Acute Disease↗
PubMed2001

Two consecutive immunophenotypic switches in a child with immunogenotypically stable acute leukaemia.

A 12-year-old girl presented with a CD33+ precursor B-acute lymphoblastic leukaemia (ALL) and seemed to respond well to ALL treatment. However, 2 weeks after diagnosis her leucocyte count rose rapidly with a predominance of myeloid blasts with M5b morphology and CD19+ myeloid immunophenotype. Acute myeloid leukaemia (AML) treatment was started and remission was achieved after one course of chemotherapy; the AML treatment was continued for 6 months. Two months after cessation of chemotherapy, the patient developed a bone marrow relapse, this time with an undifferentiated blast morphology and a precursor B immunophenotype. Molecular analysis of the immunoglobulin and T-cell receptor genes showed several clonal gene rearrangements at diagnosis: two IGH, two IGK and two TCRD gene rearrangements. All rearrangements were also detected during the AML phase of the disease, suggesting a phenotypic shift of the same leukaemia. At relapse, 8 months later, all rearrangements were preserved except for one TCRD (Vdelta2-Ddelta3) rearrangement. The first phenotypic shift in the genotypically stable leukaemia was remarkably fast. The most probable explanation for our observations is an oncogenic event in an undifferentiated haematopoietic progenitor clone, with a highly versatile phenotype.

Acute Disease↗
PubMed2001

Chromosome 13 dementia syndromes as models of neurodegeneration.

Two hereditary conditions, familial British dementia (FBD) and familial Danish dementia (FDD), are associated with amyloid deposition in the central nervous system and neurodegeneration. The two amyloid proteins, ABri and ADan, are degradation products of the same precursor molecule BriPP bearing different genetic defects, namely a Stop-to-Arg mutation in FBD and a ten-nucleotide duplication-insertion immediately before the stop codon in FDD. Both de novo created amyloid peptides have the same length (34 amino acids) and the same post-translational modification (pyroglutamate) at their N-terminus. Neurofibrillary tangles containing the classical paired helical filaments as well as neuritic components in many instances co-localize with the amyloid deposits. In both disorders, the pattern of hyperphosphorylated tau immunoreactivity is almost indistinguishable from that seen in Alzheimer's disease. These issues argue for the primary importance of the amyloid deposits in the mechanism(s) of neuronal cell loss. We propose FBD and FDD, the chromosome 13 dementia syndromes, as models to study the molecular basis of neurofibrillary degeneration, cell death and amyloid formation in the brain.

Amino Acid Sequence↗
PubMed2001

Familial cerebral amyloid angiopathy related to stroke and dementia.

The term cerebral amyloid angiopathy (CAA) refers to the specific deposition of amyloid fibrils in the walls of leptomeningeal and cortical arteries, arterioles and, although less frequently in capillaries and veins. It is commonly associated with Alzheimers disease, Down's syndrome and normal aging, as well as with a variety of familial conditions related to stroke and/or dementia: hereditary cerebral hemorrhage with amyloidosis of Icelandic type (HCHWA-I), various inherited disorders linked to Abeta mutants (including the Dutch variant of HCHWA), and the recently described chromosome 13 familial dementia in British and Danish kindreds. This review focuses on four different types of hereditary CAA, emphasizing the notion that CAA is not only related to stroke but also to neurodegeneration and dementia of the Alzheimer's type.

Alzheimer Disease↗